KR20180003897A - Document security method, device and computer readable medium - Google Patents

Abstract

The present invention relates to a method for preventing leakage of an electronic document, a device and a computer readable medium. The method for preventing leakage of an electronic document, performed by a computing device, comprises the following steps of: loading the electronic document; determining whether the loaded electronic document is a confidential document; monitoring a first leakage attempt of the electronic document when the electronic document is the confidential document; outputting a warning image, when the first leakage attempt of the electronic document is detected; monitoring a second leakage attempt of the electronic document after outputting the warning image; and outputting warning sound, when the second leakage attempt of the electronic document is detected.

Description

[0001] DOCUMENT SECURITY METHOD, DEVICE AND COMPUTER READABLE MEDIUM [0002] BACKGROUND OF THE INVENTION [0003]

The present invention relates to a method for preventing leakage of an electronic document, a device, and a computer-readable medium.

As the technological power of companies increases, the leakage of technology information is continuously increasing. For example, it often happens that an electronic document output on a screen of a computing device is secretly photographed and leaked to a personal terminal. A watermark-based security solution has emerged in which a watermark image is inserted into an electronic document and output to a screen in order to prevent such shooting attempts and to provide a surveillance to a photographer.

However, the conventional watermark-based security solution can locate the leaker in the pattern of the watermark image embedded in the photographed electronic document, but in the case of the electronic document in which the watermark image is not inserted, And it is also difficult to find the outflower.

In addition, since the conventional watermark-based security solution always overlays the watermark image in the electronic document, there is a problem that the electronic document worker inconvenience the document work.

In Korean Patent Laid-Open Publication No. 2015-0003455, while a first user who is a registered user is gazing at the iris recognition portable device, it recognizes the proximity of the first user and the second user other than the first user, A display unit of the iris recognition portable device displays a lock screen when the iris recognition unit recognizes the iris of the second user and confirms whether or not the second user is registered and the second user is identified as an unregistered user .

A warning image is output to the screen when a first outflow attempt to photograph an electronic document is detected and then a warning sound is output when a second outflow attempt to the electronic document is detected. It is to be understood, however, that the technical scope of the present invention is not limited to the above-described technical problems, and other technical problems may exist.

According to a first aspect of the present invention, there is provided a method for preventing an electronic document leakage performed by a computing device, the method comprising: loading an electronic document; determining whether the loaded electronic document is a confidential document Monitoring a first outflow attempt of the electronic document when the electronic document is a confidential document; outputting a warning image when a first outflow attempt of the electronic document is detected; Monitoring a second outflow attempt of the electronic document after outputting, and outputting a warning sound when a second outflow attempt of the electronic document is detected.

 According to a second aspect of the present invention, there is provided a device for preventing an outflow of an electronic document, comprising: a loading unit for loading the electronic document onto a screen; a determination unit for determining whether the loaded electronic document is a confidential document; A first outflow attempt monitoring unit for monitoring a first outflow attempt of the electronic document when the document is a document, a warning image output unit outputting the warning image when a first outflow attempt of the electronic document is detected, A second outflow attempt monitoring unit for monitoring a second outflow attempt of the electronic document after the warning image is output and a warning sound output unit for outputting a warning sound when a second outflow attempt of the electronic document is detected have.

The computer-readable medium may further comprise a sequence of instructions for preventing an outflow of an electronic document according to the third aspect of the present invention, the computer-readable medium being configured to cause the computing device to load an electronic document, The first output leakage attempt of the electronic document is monitored if the electronic document is the confidential document and the warning image is output when the first leakage attempt of the electronic document is detected And monitoring a second outflow attempt of the electronic document after the warning image is output, and outputting a warning sound when a second outflow attempt of the electronic document is detected.

The above-described task solution is merely exemplary and should not be construed as limiting the present invention. In addition to the exemplary embodiments described above, there may be additional embodiments described in the drawings and the detailed description of the invention.

According to any one of the above-mentioned objects of the present invention, a watermark image is not always displayed on an electronic document, but only when a mobile terminal attempting to photograph an electronic document detects (first outflow attempt) If the second outflow attempt is not detected after a predetermined period of time, the watermark image is removed from the electronic document, thereby removing elements that interfere with the document operation of the electronic document workers have.

In addition, when the second outflow attempt is detected after the detection of the first outflow attempt, since the photographing of the electronic document has been completed, a warning sound is output to further enhance the alertness of the photographer or to prevent further photographing .

In addition, if the first outflow attempt and / or the second outflow attempt is detected, the illegal photographing event information about the photographer is stored in the monitoring database, so that the outflower of the electronic document can be tracked afterwards, The source can be blocked.

1 is a configuration diagram of an electronic document leakage prevention system according to an embodiment of the present invention.
Figure 2 is a block diagram of the computing device shown in Figure 1, in accordance with one embodiment of the present invention.
3 is a diagram for explaining a method of detecting an attempt to photograph an electronic document according to an embodiment of the present invention.
4 is a view for explaining a watermark image according to an embodiment of the present invention.
5 is a diagram for explaining a device operation method upon detection of a first outflow attempt according to an embodiment of the present invention.
6 is a diagram for explaining a device operation method upon detection of a second outflow attempt according to an embodiment of the present invention.
FIG. 7 is a flowchart illustrating an exemplary method of preventing leakage of an electronic document according to an exemplary embodiment of the present invention. Referring to FIG.
FIG. 8 is a flowchart illustrating an outflow prevention method for a second outflow attempt of an electronic document according to an exemplary embodiment of the present invention. Referring to FIG.
9 is a flowchart illustrating a method for searching for illegal shooting event information according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout the specification, when a part is referred to as being "connected" to another part, it includes not only "directly connected" but also "electrically connected" with another part in between . Also, when an element is referred to as "comprising ", it means that it can include other elements as well, without departing from the other elements unless specifically stated otherwise.

In this specification, the term " part " includes a unit realized by hardware, a unit realized by software, and a unit realized by using both. Further, one unit may be implemented using two or more hardware, or two or more units may be implemented by one hardware.

In this specification, some of the operations or functions described as being performed by the terminal or the device may be performed in the server connected to the terminal or the device instead. Similarly, some of the operations or functions described as being performed by the server may also be performed on a terminal or device connected to the server.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings.

1 is a configuration diagram of an electronic document leakage prevention system according to an embodiment of the present invention.

Referring to FIG. 1, the electronic document leakage prevention system may include a computing device 100, a mobile terminal 110, and a monitoring database 120. However, since the electronic document leakage prevention system of FIG. 1 is only one embodiment of the present invention, the present invention is not limited to FIG. 1, have. For example, the monitoring database 120 may reside within the computing device 100.

Generally, each component of the electronic document outflow prevention system of FIG. 1 is connected through a network 130. A network refers to a connection structure in which information can be exchanged between nodes such as terminals and servers. An example of such a network is Wi-Fi, Bluetooth, Internet, LAN Network, wireless LAN, WAN, PAN, 3G, 4G, 5G, LTE, and the like.

The computing device 100 may be a device with an anti-shake solution installed on the electronic document loaded into the computing device 100.

The computing device 100 detects in real time a first outflow attempt (illegal capturing attempt) of the electronic document through the camera 101 mounted on the computing device 100, and when the first outflow attempt is detected, A warning image can be output.

When the first outflow attempt is detected, the computing device 100 transmits the illegal capture event information for the first outflow attempt (detection time information of the first outflow attempt, the image of the photographer who took the electronic document and the image of the mobile terminal ), And transmit the generated illegal shooting event information to the monitoring database.

The computing device 100 detects in real time a second outflow attempt (illegal capture completion) of the electronic document via the microphone (not shown) of the computing device 100 after the first outflow attempt is detected, If a car outflow attempt is detected, it is considered that the illegal capture has been completed, the security manager is informed of the second outflow attempt, and a warning sound may be output through the speaker (not shown) of the computing device 100.

When the second outflow attempt is detected, the computing device 100 generates the illegal shooting event information (the detection time information of the second outflow attempt, the shutter sound of the mobile terminal) for the second outflow attempt, The photographing event information can be transmitted to the monitoring database.

Computing device 100 may include a variety of devices capable of working with electronic documents, and in accordance with various embodiments of the present invention, computing device 100 may be, for example, a personal computer, a notebook computer Notebook) and the like. The computing device 100 may also include various devices capable of outputting confidential content in addition to electronic documents. For example, the computing device 100 may include a set-top box, a TV, a mobile terminal, and the like. Here, the mobile terminal 110 may be a portable terminal equipped with a photographing device. The portable terminal may or may not be a device capable of communicating. For example, the portable terminal may be a Personal Communication System (PCS), a Global System for Mobile communications (GSM), a Personal Digital Cellular (PDC), a Personal Handyphone System (PHS), a Personal Digital Assistant (PDA), an International Mobile Telecommunication (IMT) -2000, Code Division Multiple Access (CDMA) -2000, W-CDMA (W-CDMA), Wibro (Wireless Broadband Internet) terminals, smart phones, tablet PCs, Handheld-based wireless communication devices. In addition, the mobile terminal 110 may include all devices capable of photographing (digital camera, camcorder, smart glass, etc.). However, the computing device 100 is not limited to the form shown in Figure 1 or to those illustrated above.

The monitoring database 120 may store illegal photographing event information including at least one of detection time information of a shutter sound and a shutter sound, a photographed image, and detection time information of a mobile terminal for each electronic document.

The surveillance database 120 may be used to retrieve or query information related to illegal shooting sites in the event of an illegal outflow of an electronic document

Hereinafter, the operation of each component of the electronic document leakage prevention system of FIG. 1 will be described in more detail. 2 is a block diagram of computing device 100 shown in FIG. 1, in accordance with one embodiment of the present invention.

2, the computing device 100 includes a loading unit 200, a determination unit 210, a first outflow attempt monitoring unit 220, a photographing unit 230, a watermark image generating unit 240, A warning image output unit 250, a second outflow attempt monitoring unit 260, a warning sound output unit 270, an illegal photographing event information generating unit 280, and a transmitting unit 290. However, the computing device 100 shown in FIG. 2 is only one embodiment of the present invention, and various modifications are possible based on the components shown in FIG.

The loading unit 200 can load an electronic document through a document application. For example, the loading unit 200 can load an electronic document in response to a user's operation to command opening of the electronic document. Here, the document application may be one of various commercial applications.

The determination unit 210 may determine whether the loaded electronic document is a confidential document. For example, the judging unit 210 judges whether or not the document attribute field of the loaded electronic document (for example, including '1' in the attribute field in case of a confidential document, and '0' ) Or whether or not the electronic document is a confidential document based on whether encryption is set or not.

The first outflow attempt monitoring unit 220 can monitor the first outflow attempt of the electronic document when the electronic document is classified document. For example, the first outflow attempt monitoring unit 220 may monitor whether the mobile terminal 110 exists in the field of view of the camera 101 of the computing device 100. Mobile terminal 110 refers to a device that is capable of taking an electronic document loaded into computing device 100.

The first outflow attempt monitoring unit 220 may detect the mobile terminal 110 attempting to shoot an electronic document through the camera 101 of the computing device 100. [ Here, the detection method of the mobile terminal 110 may be selected from various conventional techniques. For example, the first outflow attempt monitoring unit 220 learns the external features of the mobile terminal 110 (e.g., type information of the mobile terminal 110, edge information, color information, etc.) It is possible to detect the mobile terminal 110 attempting to take a picture.

A method for detecting a photographing attempt of the mobile terminal 110 will be described with reference to FIG. 3 for a while. 3 is a diagram for explaining a method of detecting an attempt to photograph an electronic document according to an embodiment of the present invention.

3 is a block diagram illustrating a mobile terminal 110 and a display device (a computing device 100) on which a camera 101 is mounted, illustrating an electronic document output on a screen of a notebook (computing device 100) (31) illustrating a mobile terminal (110) that scans an electronic document output on a screen of a mobile terminal (110).

Referring to FIG. 3, in order to photograph an electronic document through the mobile terminal 110, a photographing region is selected and a lens is focused on the photographing region. In this process, the mobile terminal 110 enters the field of view of the camera 101 of the computing device 100. The computing device 100 may detect that the mobile terminal 110 is attempting an illegal capture when the mobile terminal 110 is detected.

2, the photographing unit 230 may photograph the photographer and the mobile terminal 110 through the camera 101 when the mobile terminal 110 is detected. For example, the photographing unit 230 can detect the face of the photographer through the face detector, and photograph the face of the photographer and the mobile terminal 110 attempting to photograph the electronic document.

The watermark image generating unit 240 may generate a watermark image. For example, the watermark image generating unit 240 may generate a conditional watermark image, and may generate a visible watermark image or an invisible watermark image. Here, the conditional watermark image may be an image including a function of causing the watermark image to disappear from the electronic document if a leakage attempt of the electronic document is not detected again within a predetermined time.

Referring to FIG. 4, the watermark image may include various types of patterns such as a code or a type specific to a sign such as an ID or an ID, or a signal such as information, which is known only to a user of the electronic document 401 Lt; / RTI > Such a watermark image may include, for example, a pattern of a barcode 403, a QR code 405, a color box pattern 407, a character pattern 409, and the like.

Referring again to FIG. 2, the warning image output unit 250 may output a warning image to the screen of the computing device 100 when a first outflow attempt of the electronic document is detected. For example, the warning image output unit 250 can overlay the generated watermark image on the electronic document when the mobile terminal 110 attempting to photograph is detected. By outputting the watermark image to the electronic document, the user can be notified that the electronic document is important content or secret content. Accordingly, the user's awareness of the security of the electronic document can be enhanced.

The second outflow attempt monitoring unit 260 may monitor the second outflow attempt of the electronic document after the warning image is displayed on the screen of the computing device 100. [ The second outflow attempt monitoring unit 260 can detect the shutter sound of the mobile terminal 110 through the microphone (not shown) of the computing device 100. [

The warning sound output unit 270 may output a warning sound when a second outflow attempt of the electronic document is detected. In other words, since the situation in which the shutter sound of the mobile terminal 110 is detected means that the mobile terminal 110 has already finished shooting, the warning sound output unit (not shown) is activated to further awaken the alertness of the photographer, 270) can output a warning sound as a secondary warning.

The illegal shooting event information generating unit 280 may generate the illegal shooting event information based on the detection information of the first outflow attempt (photographing attempt of the mobile terminal 110). The illegal photographing event information generating unit 280 may generate illegal photographing event information including the detection time information of the mobile terminal 110 and the ID of the electronic document together with the image of the detected mobile terminal 110 and the photographer .

The illegal shooting event information generating unit 280 may generate the illegal shooting event information based on the detection information of the second outflow attempt (shutter sound of the mobile terminal 110). The illegal shooting event information generating unit 280 may generate illegal shooting event information including detection time information of the shutter sound and the shutter sound of the detected mobile terminal 110, and the ID of the electronic document.

When the first outflow attempt of the mobile terminal 110 is detected, the transmission unit 290 may transmit the illegal capture event information for the first outflow attempt to the monitoring database. When the second outflow attempt is detected after the first outflow attempt is detected, the transmitter 290 may transmit the illegal capture event information for the second outflow attempt to the surveillance database.

The memory unit (not shown) stores data that is input and output between each component in the computing device 100 and is input and output between components outside the computing device 100 and the computing device 100 And stores the data. One example of such a memory unit (not shown) includes a hard disk drive, a ROM (Read Only Memory), a RAM (Random Access Memory), a flash memory, a memory card, and the like existing inside or outside the computing device 100.

A person skilled in the art will appreciate that the loading unit 200, the determining unit 210, the first outflow attempt monitoring unit 220, the photographing unit 230, the watermark image generating unit 240, the warning image outputting unit 250, The second outflow attempt monitoring unit 260, the warning sound output unit 270, the illegal photographing event information generating unit 280, and the transmitting unit 290 may be separately implemented, or at least one of them may be integrated It will be appreciated.

5 is a diagram for explaining a device operation method upon detection of a first outflow attempt according to an embodiment of the present invention. 5, when an attempt is made to photograph an electronic document 501 by the mobile terminal 110, the computing device 100 overlays and prints a watermark image 503 on the electronic document 501, The image of the photographer 505 and the image 507 of the mobile terminal 110 may be photographed and transmitted to the monitoring database 300 to record the status information at the time of the first outflow attempt.

The watermark image 503 overlaid on the electronic document 501 may disappear after a predetermined period of time after the detection of the first leakage attempt.

6 is a diagram for explaining a device operation method upon detection of a second outflow attempt according to an embodiment of the present invention.

6, when the shutter sound of the mobile terminal 110 is detected through the built-in microphone 620 of the computing device 100, the computing device 100 displays illegal photographing event information indicating that the illegal photographing is completed The detection time information of the sound and the shutter sound) to the monitoring database 120, outputs a warning sound for inhibiting further shooting through the built-in speaker 610, or outputs the second warning message 630 to the screen .

FIG. 7 is a flowchart illustrating an exemplary method of preventing leakage of an electronic document according to an exemplary embodiment of the present invention. Referring to FIG.

The outflow prevention method according to the embodiment shown in FIG. 7 includes steps that are performed in a time-series manner in the computing device 100, the mobile terminal 110, and the monitoring database 120 according to the embodiment shown in FIGS. . Accordingly, the contents described with respect to the computing device 100, the mobile terminal 110, and the monitoring database 120 of FIGS. 1 through 6 are not limited to the leakage prevention method according to the embodiment shown in FIG. 7, Can be applied.

Referring to FIG. 7, in step S701, the computing device 100 may load an electronic document. In step S703, the computing device 100 can determine whether the loaded electronic document is confidential.

In step S705, if the electronic document is a confidential document, the computing device 100 may determine whether there is a mobile terminal 110 to attempt to shoot (first outflow) the electronic document.

In step S707, the computing device 100 may generate a watermark image if a first outflow attempt of the electronic document is detected. In step S709, the computing device 100 can overlay the generated watermark image on the electronic document and output it.

In step S711, the computing device 100 may photograph the photographer and the mobile terminal 110 via the camera 101 when the mobile terminal 110 is detected. The computing device 100 may send illegal capture event information to the surveillance database 120 that includes the captured image (image of the photographer and the mobile terminal 110) and detection time information of the mobile terminal 110 in step S713 .

In the above description, steps S701 to S713 may be further divided into further steps or combined into fewer steps, according to an embodiment of the present invention. Also, some of the steps may be omitted as necessary, and the order between the steps may be changed.

FIG. 8 is a flowchart illustrating an outflow prevention method for a second outflow attempt of an electronic document according to an exemplary embodiment of the present invention. Referring to FIG.

The outflow prevention method according to the embodiment shown in FIG. 8 includes steps that are performed in a time-series manner in the computing device 100, the mobile terminal 110, and the monitoring database 120 according to the embodiment shown in FIGS. . Accordingly, the contents described with respect to the computing device 100, the mobile terminal 110, and the monitoring database 120 of FIGS. 1 through 7 are not limited to the leakage prevention method according to the embodiment shown in FIG. 8 Can be applied.

Referring to FIG. 8, in step S801, the computing device 100 may monitor a second outflow attempt of an electronic document after a warning image due to a first outflow attempt of the mobile terminal 110 is output.

In step S803, the computing device 100 may output a warning sound when the shutter sound of the mobile terminal 110 is detected (second outflow attempt) through the microphone of the computing device 100. [

In step S805, the computing device 100 may generate illegal shooting event information including detection time information of the shutter sound and the shutter sound of the mobile terminal 110. [ In step S807, the computing device 100 may transmit the generated illegal shooting event information to the monitoring database.

In the above description, steps S801 to S807 may be further divided into further steps or combined into fewer steps, according to an embodiment of the present invention. Also, some of the steps may be omitted as necessary, and the order between the steps may be changed.

9 is a flowchart illustrating a method for searching for illegal shooting event information according to an embodiment of the present invention.

The illegal shooting event information retrieving method according to the embodiment shown in FIG. 9 is performed in a time-wise manner in the computing device 100, the mobile terminal 110 and the monitoring database 120 according to the embodiment shown in FIGS. 1 to 8 ≪ / RTI > Therefore, the content described with respect to the computing device 100, the mobile terminal 110, and the monitoring database 120 in FIGS. 1 to 8 is not limited to the illegal shooting event information according to the embodiment shown in FIG. 9, It can also be applied to a search method.

Referring to FIG. 9, in step S901, the computing device 100 or another administrator terminal (not shown) may receive an illegal photograph event information request for a specific electronic document when a specific electronic document is illegally leaked.

In step S903, the computing device 100 or another administrator terminal (not shown) receives illegal photographing event information for a specific electronic document from the monitoring database and inquires information related to the photographing site of the electronic document.

In the above description, steps S901 to S903 may be further divided into further steps or combined into fewer steps, according to an embodiment of the present invention. Also, some of the steps may be omitted as necessary, and the order between the steps may be changed.

One embodiment of the present invention may also be embodied in the form of a recording medium including instructions executable by a computer, such as program modules, being executed by a computer. Computer readable media can be any available media that can be accessed by a computer and includes both volatile and nonvolatile media, removable and non-removable media. In addition, the computer-readable medium may include both computer storage media and communication media. Computer storage media includes both volatile and nonvolatile, removable and non-removable media implemented in any method or technology for storage of information such as computer readable instructions, data structures, program modules or other data. Communication media typically includes any information delivery media, including computer readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave, or other transport mechanism.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

It is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. .

100: computing device
101: camera of computing device
110: mobile terminal
120: Surveillance database

Claims (17)

A method for preventing electronic document outflow performed by a computing device,
Loading an electronic document;
Determining whether the loaded electronic document is a confidential document;
Monitoring a first outflow attempt of the electronic document when the electronic document is a confidential document;
Outputting a warning image when a first outflow attempt of the electronic document is detected;
Monitoring a second outflow attempt of the electronic document after the warning image is output; And
When a second outflow attempt of the electronic document is detected, outputting a warning sound
And an electronic document leakage prevention method.
The method according to claim 1,
The step of outputting the warning image
Generating a watermark image; And
And overlaying the generated watermark image on the electronic document and outputting the watermark image.
The method according to claim 1,
Wherein monitoring the first outflow attempt of the electronic document comprises:
Detecting a mobile terminal attempting to shoot the electronic document via a camera of the computing device
The electronic document leakage prevention method comprising:
The method of claim 3,
Wherein monitoring the second outflow attempt of the electronic document comprises:
Detecting a shutter sound of the mobile terminal through a microphone of the computing device
The electronic document leakage prevention method comprising:
5. The method of claim 4,
Further comprising the step of transmitting illegal photographing event information to a monitoring database when a shutter sound of the mobile terminal is detected,
Wherein the illegal photographing event information includes detection time information of the shutter sound and the shutter sound.
The method of claim 3,
Photographing the photographer and the mobile terminal through the camera when the mobile terminal is detected;
Transmitting illegal photographing event information including the photographed image and detection time information of the mobile terminal to a monitoring database
Further comprising the steps of:
The method according to claim 1,
Generating illegal photographing event information based on at least one of detection information of the first outflow attempt and detection information of the second outflow attempt; And
Transmitting the illegal shooting event information to a monitoring database
The electronic document leakage prevention method further comprising:
8. The method of claim 7,
Receiving an illegal photographing event information request for the electronic document; And
Receiving illegal photographic event information for the electronic document from the monitoring database
The electronic document leakage prevention method further comprising:
A device for preventing leakage of an electronic document,
A loading unit loading the electronic document onto a screen;
A determining unit determining whether the loaded electronic document is a confidential document;
A first outflow attempt monitoring unit for monitoring a first outflow attempt of the electronic document when the electronic document is the confidential document;
A warning image output unit outputting the warning image when a first outflow attempt of the electronic document is detected;
A second outflow attempt monitoring unit for monitoring a second outflow attempt of the electronic document after the warning image is output;
A warning sound output unit for outputting a warning sound when a second outflow attempt of the electronic document is detected,
/ RTI >
10. The method of claim 9,
Further comprising: a watermark image generating unit generating a watermark image,
The warning image output unit
And overlaying and outputting the generated watermark image on the electronic document.
10. The method of claim 9,
The first outflow attempt monitoring unit
And detects a mobile terminal attempting to photograph the electronic document via a camera of the device.
12. The method of claim 11,
The second outflow attempt monitoring unit
And detects a shutter sound of the mobile terminal through a microphone of the device.
13. The method of claim 12,
An illegal shooting event information generating unit for generating illegal shooting event information based on at least one of the detection information of the first outflow attempt and the detection information of the second outflow attempt;
And a transmitting unit for transmitting the illegal photographing event information to a monitoring database.
14. The method of claim 13,
Wherein the illegal shooting event information includes detection time information of the shutter sound and the shutter sound.
14. The method of claim 13,
And a photographing unit photographing the photographer and the mobile terminal through the camera when the mobile terminal is detected,
Wherein the illegal shooting event information includes the captured image and detection time information of the mobile terminal.
14. The method of claim 13,
Wherein the monitoring database stores illegal photographing event information including at least one of detection time information of the shutter sound and the shutter sound, the captured image, and detection time information of the mobile terminal for each electronic document.
15. A computer readable medium comprising a sequence of instructions for preventing an outflow of an electronic document,
When executed by a computing device,
Loading an electronic document,
Judges whether the loaded electronic document is a confidential document,
If the electronic document is the confidential document, monitoring a first outflow attempt of the electronic document,
Outputting a warning image when a first outflow attempt of the electronic document is detected,
Monitoring a second outflow attempt of the electronic document after the warning image is output,
And to output a warning sound when a second outflow attempt of the electronic document is detected.

Images